New Double Complex Salts [M(im)_n][RuNOCl₅] (M = Ni, Cu): Synthesis, Structure, and Thermal Properties

Procedures for the synthesis of new double complex salts [Cu(im)₄][RuNOCl₅], [Ni(im)₆][RuNOCl₅]·H₂O, and p-[Ni(im)₄(DMF)₂][RuNOCl₅] have been developed and their crystal structure have been determined. Thermal properties of the synthesized DCS have been studied under inert and reducing atmospheres using synchronous TG–DTA and ex situ XRD of intermediate and final thermolysis products. It has been found that thermal decomposition occurs in three stages. Thermolysis of [Cu(im)₄][RuNOCl₅] under inert and reducing atmospheres gives rise to the mixture of copper and ruthenium, while the thermal decomposition of [Ni(im)₆][RuNOCl₅]·H₂O under an inert atmosphere results in a mixture of nickel and ruthenium. A supersaturated Ni_0.27Ru_0.73 solid solution can be obtained in the nickel-ruthenium system upon thermolysis under a reducing atmosphere at temperature up to 400°C. Increase in thermolysis temperature up to 800°C leads to the partial decomposition of the solid solution.